The generation of a microwave signal at a desired frequency is usually implemented using a circuit with a phase-locked loop. Such a circuit makes it possible to slave the frequency of the output signal to a multiple of the frequency of the reference signal. The output frequency may thus be chosen from several values solely by modifying the frequency division value of the feedback loop. One drawback of such a circuit is that it generates significant phase noise on the output signal. In fact, the output phase noise is increased by a factor equal to the division factor of the phase loop compared with the phase noise of the reference signal.